This invention relates to pharmacologically useful compositions.
In British Pat. No. 705,979 there are described a number of unsymmetrical 1,4-diaralkyl piperazines. In particular such piperazines may have as the aralkyl substituent upon one nitrogen atom a p-halobenzhydryl group and as the aralkyl substituent upon the second nitrogen atom a benzyl or an alkyl- or dialkyl-benzyl group the alkyl group or groups being present as the substituent or substituents in the benzene ring. Such compounds have been recognised to possess properties characteristic of an antihistamine. Nevertheless such compounds have been found to possess properties unusual in an antihistamine, for example, their prolonged period of activity which, in relation to typical antihistamine properties has been shown to persist for a number of days. Thus in relation to guinea pigs it has been shown that 1-p-chlorobenzhydryl-4-p-tertiary butyl-benzyl piperazine gives protection against histamine in the form of an aerosol for as long as 16 days.
Antihistamines are administered primarily to give protection against various conditions which are recognized to have an allergic origin and, upon the basis that certain patients suffering from migraine do so as the result of an allergic reaction to food which they have consumed, a limited investigation has been reported in which migraine induced by the consumption of food was sought to be prevented by the prophylactic administration of 1-p-chlorobenzhydryl-4-p-tertiary-butyl-benzyl piperazine: prevention was however claimed in but a single case and as a pain-reducing agent the treatment was regarded as unsuccessful. Elsewhere it has been stated that antihistamines are valueless in the treatment of migraine.
It is an object of the invention to provide a pharmaceutical composition of substantially non-toxic character which can be taken by patients who suffer from migraine with at least a reasonable prospect of obtaining relief or, if taken in time, to prevent the occurrence of a migraine attack.